The invention relates to a fastening arrangement for a safety belt, comprising a holder that is to be secured to a vehicle, and a connector that is moveably disposed, against spring action, on the holder, and is connected to a belt buckle or a belt strap loop, whereby a magnet and a magnetic field sensor are disposed on the holder and connector, and the relative movement between magnet and magnetic field sensor caused by displacement of the connector relative to the holder, which displacement is effected by the tension acting on the belt buckle, is converted into a signal that corresponds to the acting belt force.
A fastening arrangement having the aforementioned features and provided for a belt buckle is described in WO 01/79039 A1; such a fastening arrangement for a safety belt buckle, and provided with a sensor arrangement, serves for determining the belt force that respectively occurs in the safety belt system under various stress conditions, in order as a function of the measured belt force to control further components of the safety system, such as, for example, airbag devices.
With the known fastening arrangement, formed in the holder that is secured on the vehicle side is a region within which is moveably disposed a carriage that is guided on the holder; at least one compression spring disposed between holder and carriage tensions the carriage relative to the holder and enables a displacement of the carriage in the holder portion in conformity with the spring path. The connector that is connected with the belt buckle is embodied as a loop that extends through the portion of the holder and thereby spans the outer contour of the carriage that is moveable in the holder portion in such a way that a tension force that acts upon the connector brings about a displacement of the carriage in the portion of the holder against the force of the compression spring. Mounted on the holder and carriage, in a cooperative association, are a magnet and a magnetic field sensor, so that the relative movement of carriage and holder to one another in conformity with the respectively occurring belt force is to be detected via the change of the magnetic field that is received by the magnetic field sensor, and is capable of being converted in a microprocessor into a suitable signal for the control of further components of the vehicle safety system.
The known fastening arrangement has the drawback of a complicated construction and a cumbersome assembly. For example, the holder, and the carriage that is moveably guided therein, must be produced with the necessary precision and must be assembled together with the springs, whereby the assembly or mounting of the carriage on the holder is cumbersome due to the compression springs that are disposed within the portion of the holder. The connector, with its loop, must then be guided through the recess of the holder in a further assembly step, and in so doing must be oriented relative to the carriage, whereby the loop must again be reliably closed at the conclusion of the assembly.
It is therefore an object of the invention to simplify the construction and assembly of a fastening arrangement having the aforementioned features.